Fabricated gear and winding drum



NOV. 15, 1955 J w so FABRICATED GEAR AND WINDING DRUM 5 Sheets-Sheet 1 Filed March 9, 1953 Ila (v2 ((97 x72 5 [ZZZ/5012 Nov. 15, 1955 Filed March 9, 1953 J. WILSON 2,723,832

FABRICATED GEAR AND WINDING DRUM 3 Sheets-Sheet 2 I i v fizz erziww 1 7 QCZYG'IZ W wn v JVIMWU Nov. 15,1955 J. WILSON 2,723,832

FABRICATED GEAR AND WINDING DRUM Filed March 9, 1953 Y 3 Sheets-Sheet 3 Jiaverzfion I f ck ZQ/Jarz 777 1 5W1 rim United States Patent ()fiice 2,723,832 Patented Nov. 15, 1955 2,723,832 I FABRICATED GEAR AND WINDING DRUM Jack Wilson, Chicago, Ill., assignor to Universal Railway Devices 00., a corporation of Delaware Application March 9, 1953, Serial No. 341,189

Claims. (Cl. 254149) Gears and winding drums for hand wheel brakes of railroad cars are commonly malleable iron castings, and frequently contain familiar defects that cannot be or are not found by usual inspection; for example, blow holes, pockets, sand holes, cracks, and warps. 1

As a result, there are failures, such as gear teeth breaking out, causing serious accidents that may be illustrated by the wild car running down a street in Los Angeles a short time ago.

To make malleable cast gears and drums, the castings must be taken out of the sand molds while at high heat and put into furnaces to cool slowly, after which they are put in annealing furnaces for ten days or more, and the number of usable castings to be obtained from a given lot cannot be predicted with certainty for best production. Loss of thirty out of one hundred is frequent, and loss of a whole lot of castings is a none too rare experience.

Hand brakes, being safety appliances, should give maximum safety obtainable at permissible cost of production.

The principal object of this invention is to overcome these and many other defects with the long used devices and practices, and provide uniform high-grade accurate and durable gears and winding drums to replace malleable castings in new equipment and in old hand brakes now in cars.

Generally speaking, this is accomplished by fabricating gears and winding drums of wrought metal parts, such as a gear plate having forged teeth at the periphery, a tubular hub welded in a central opening in the plate, and a chain anchor and guide welded to the hub and securely braced to the gear plate. In this way, manufacturing tolerances can be kept close to designs making for accurate cooperation in the assembled devices and strength and surface hardness of parts had by using steels of selected compositions.

Further objects and advantages of the invention will appear as the description is read in connection with the accompanying drawings, in which Fig. l is a fragmentary sectional view of so much of a hand brake mechanism as is necessary to show the atmosphere in which the combined gear and winding drum is used;

Fig. 2 is an enlarged view of the combined gear and winding drum, the parts being broken away;

Fig. 3 is a fragmentary sectional view showing a portion of the chain in place;

Fig. 4 is a side elevation of a combined chain anchor and chain guide forming one of the elements of the device;

Fig. 5 is an edge view of the same looking from the bottom of Fig. 4;

Fig. 6 is a side elevation of the gear and winding drum seen from the left of Fig. 2 with parts broken. away;

Fig. 7 is a part elevation and part section looking from the bottom of Fig. 6;

Fig. 8 is a view of the constituent elements of the gear and winding drum displaced from the positions they assume after assembly; and

Fig. 9 is an elevation of the gear plate looking from the left in Fig. 8.

But these specific drawings and the corresponding description are used for the purpose of illustrative disclosure only, and are not intended to impose unnecessary limitations on the claims.

In Fig. l, 10 indicates a hand wheel mounted on a hand wheel shaft 11 journalled at 12 and 13 in a casing composed of an inner body portion 14 and an outer cover portion 15. The shaft 11 is provided with a ratchet 16 and a pinion 17 meshing with teeth 18 of a larger gear 19 having a hub and winding drum 20 journalled at 21 in the casing body 14 and at 22 on the cover plate 15.

The gear 19 is composed of a plate having inwardly and outwardly dished portions 23 and 24 surrounded by a rim 25 and integral with an inner ring 26 having a central opening 27. The outwardly dished portion 24 has an opening 28 to receive a rivet or bolt for fastening a link of the chain 29.

The hub, generally indicated by 30, is tubular having a drum portion 20 and enlarged end portions 31 and 32. In assembly, the enlarged portion 31 is received within the central opening 27 of the gear plate and welded all around to the central ring 26 as indicated at 33.

The chain anchor and guide, generally indicated by 35, has substantially the form of a segment of a spiral vane with radial flaring edges 36 and 37 (Fig. 4) connecting small arc 38 and large are 39, there being a curved fillet 40 between the edge 37 and the are 39.

In assembly, the edge 36 is welded to the outwardly dished portion 24 as indicated at 41, and the are 38, which is really a spiral, is welded to the intermediate portion 20 of the hub as indicated at 42 (Fig. 2)

The area in the neighborhood of the curved fillet 40 is thickened as indicated at 43 and provided with an opening 44 aligned with the opening 28 in the gear plate to receive the chain fastening rivet 45.

The intermediate portion of the chain anchor and guide is provided with an integral brace 46, the end of which comes against the outwardly dished portion 24 and is welded to it as indicated at 47 (Figs. 2, 3, and 7).

The gear teeth 18 are formed on the rim 25 of the gear plate by forging in accordance with the process disclosed in my application Ser. No. 154,949, filed April 10, 1950. The plate is made of wrought steel of a composition which lends itself to such hardening of the gear teeth as may be found desirable.

The hub is preferably a steel forging, so it may be made by swaging steel tubing. The enlarged ends 31 and 32 are provided with brass bushings 48 for cooperation respectively with the elements 14 and 15 of the casing, as best shown in Fig. l.

The chain anchor and guide is a steel forging affording a strong fastening for the chain rivet 45 and providing a guide for directing the winding of the chain as the brakes are applied by turning the hand wheel 10. The brace 46 and the thickened portion 43 give it the necessary strength to withstand the strains of the chain pressure in operation.

I claim:

1. In a fabricated gear and winding drum for hand brakes, a tubular hub having an intermediate drum portion and a bearing portion at each end, a gear plate having a central opening receiving the tubular hub and welded to it about said opening, and a chain anchor and guide plate having a substantially straight edge welded to the gear plate and a spiral edge welded to the tubular hub, said chain anchor and guide plate having a brace spaced from the hub, projecting parallel thereto and welded at its outer end to the gear plate.

2. In a fabricated gear and winding drum for hand brakes, a tubular hub having an intermediate drum portion and a bearing portion at each end, a gear plate having a central opening receiving the tubular hub and welded to it about said opening, and a chain anchor and guide plate having an edge welded to the gear plate and a spiral edge welded to the tubular hub, said chain anchor and guide plate having a chain guide portion extending away from the tubular hub and the gear plate and a brace spaced from the hub and fastened to the gear plate.

3. In a fabricated gear and winding drum for hand brakes, a tubular hub having an intermediate drum portion and a bearing portion at each end, a gear plate having inwardly and outwardly dished portions and a central opening receiving the tubular hub and welded to it around said opening, and a chain anchor and guide plate having an edge welded to the outwardly dished portion of the gear plate and a spiral edge welded to the tubular hub, said chain anchor and gear plate having a chain guide portion extending way from the tubular hub and gear plate and a brace spaced from the hub and fastened to the outwardly dished portion of the gear plate! 4. In a fabricated gear and winding drum for hand brakes, a tubular hub having an intermediate drum portion and a bearing portion at each end, a gear plate having a central opening receiving the tubular hub and welded to it about said opening, and a chain anchor and guide plate having a spiral edge welded to the tubular hub and a chain guide portion extending away from the tubular hub and the gear plate, said chain anchor and guide plate having a brace spaced from the hub and fastened to the gear plate.

5. In a fabricated gear and winding drum for hand brakes, a chain anchor and guide member having substantially the form of a segment of a spiral vane bounded by a pair of flaring edges and spaced inner and outer arcs, connecting the opposite ends of said flaring edges, said member including a reinforced bolt-opening at one end thereof and parallel to the axis of the spiral, and a reinforcing boss projecting from the vane in a direction parallel to the axis of the spiral and spaced from said opening and adapted to bear against the winding drum.

References Cited in the file of this patent UNITED STATES PATENTS 488,001 French Dec. 13, 1892 925,466 Dixon June 22, 1909 2,152,376 Endicott Mar. 28. 1939 

